How do food jar factories put negative pressure into the jar to begin with?

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How do food jar factories put negative pressure into the jar to begin with?

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Anonymous 0 Comments

Old-school canning preserves food by killing every damn thing in there in step one (below) and then creating a low pressure/oxygen environment in step two to make sure nothing that nothing can grown (even though every damn thing is already dead). The current way they do things is still similar-

1. put your old school style mason jars with whatever you want to can/pickle in it in a warm water bath (at least 180 degrees). Let them sit in there a while, and let all those little bastards microbes die a terrible death.
2. Once the fuckers are dead, you put the frisbee looking circle part of the mason jar lid in place, then put the outer ring in place and close it up. The gas in there is hot, and mostly steam.
3. Once everything cools the frisbee will “pop” down, because the hot steamy gas of death in there was higher pressure when hot, but has cooled to a lower pressure than the outside air, and there is a slight vacuumed that results in the pop/sucking down of the frisbee.

The result is something that is very sterilized, and also not a place where new microbes will be able to easily grow if they did manage to somehow get in or survive.

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